Failed authorization procedure. server1.realdomain.com (http-01): urn:acme:error:connection :: The server could not connect to the client to verify the domain :: DNS problem: NXDOMAIN looking up A for server1.realdomain.com
To fix these errors, please make sure that your domain name was
entered correctly and the DNS A/AAAA record(s) for that domain
contain(s) the right IP address. Additionally, please check that
your computer has a publicly routable IP address and that no
firewalls are preventing the server from communicating with the
client. If you’re using the webroot plugin, you should also verify
that you are serving files from the webroot path you provided.
My web server is (include version):
nginx/1.12.2
The operating system my web server runs on is (include version):
CentOS Linux release 7.4.1708
My hosting provider, if applicable, is:
my cloud
I can login to a root shell on my machine (yes or no, or I don’t know):
Yes
I’m using a control panel to manage my site (no, or provide the name and version of the control panel):
no
You will need a real domain (e.g public registered, not local) and (public resolvable DNS server or public accessible domain) to generate a cert for your server.
Yeah, that error means that Let’s Encrypt couldn’t find a DNS record (A or AAAA record) for your domain name. You need to make one. If you think you have this, you’d need to provide the actual domain name for anyone to be able to help you.
I assume with "connectable", you mean to be able to connect to the destination IP? Because that's not true, you can get a certificate for a private IP, as long as the domain name is real. You can use the DNS challenge, it only needs a publically accessable DNS server.
Hi! Thnx for your answers. I want clarify:
I want create cert for myserver.tut.by and real only tut.by. Myserver.tut.by it is internal name and have internal ip.